Today a greater number of mines are going deeper underground. This often means investing in larger ventilation fans with increased air pressure throughout the mine. Controlling air flow with strategically placed ventilation doors is essential to operating an efficient ventilation control plan. Higher air pressures can also mean higher safety risks. In turn, safety concerns at the ventilation door location cannot be overlooked.  

Consider all potential safety risks when choosing the correct ventilation doors system. Beyond the obvious safety questions and analysis, below are a few additional questions to evaluate when choosing a safe door system:

• Have your proposed ventilation door designs been engineered to your very specific application?
• Higher Air Pressures equals Higher Risk. Are the door designs certified by a PE to exceed these increasing air pressures conditions? No longer can this be left to chance.
• Have your ventilation door designs been FEA analyzed to safely handle these higher pressures? With mine safety at the forefront of everyone at the mine, it is just too much of a risk to proceed with just a leap of faith.
• When purchasing new ventilation doors, has the mine considered long-term ventilation pressure expectations? Before a mine increases WG pressure within the mine, has an evaluation of all existing doors been considered?
• With automated vent doors, has the actuation system been engineered and approved to exceed all force / buckling requirements? What are those specifications? What is the impact on the door in the event an actuator buckles or fails?
• In the event of a malfunction or loss of power event, how will doors react? This is often overlooked and critical to miner safety. Doors slamming shut can have serious consequences to miner safety.

A Safer Balanced Door Design

The AMD Opposing Wing Door Design has accounted for all the above. The AMD Opposing Wing Door Design uses the mines existing air pressure to assist with the opening and closing of the doors. One door wing opens against the air flow while the opposite door wing opens with the air flow. They are balanced. In this design the same amount of air pressure that is resisting one door wing panel, will provide equal and opposite air pressure assisting the other door wing panel. This unique design takes advantage of equalized air pressure to assist the door in opening and closing and will maintain its current position in any malfunction scenario.

Both door wings are connected with a top mounted connecting bar. By using the energy of the existing air pressure, this door design requires minimal efforts to open/close. One actuation cylinder is enough to open and close even a very large mine door. Most importantly in the event of malfunction or loss of power event, the doors will remain in whatever state they were in at the time of the event. They are balanced. Doors slamming shut or lunging open will not occur. That is peace of mind when comes to large doors under high pressure.

Example of Balanced Air Pressure Door

See the AMD Opposing Wing Door Design animation here

Safety Built Into the Design

If there were ever a failure of the actuation cylinder, or loss of power at the door, the AMD Opposing Wing Door is designed to remain in position and not lung open or slam closed.  A significant safety feature. Remember, there is equal and opposite pressure that negates movement of the doors. Doors will not slam shut or lung open. Other traditional door designs have both door wing panels opening or closing in the same direction. Not AMD. The “barn door” traditional style doors do not have the same safety advantages of the Opposing Wing Door Design that proves out to be a much safer door design. In addition, the other “same directional” doors generally requires two actuation cylinders, one for each door wing panel. As described above the AMD’s Opposing Wing Door requires only one actuation cylinder as shown above and in video.

AMD Mine Door Safety Engineering

The Opposing Wing Door Design was patented by AMD in the early 1900’s. AMD has since gone through years and decades of improvements. However, AMD never takes safety for granite. AMD’s technical engineering will scrutinize each and every door project to ensure the amount of force placed upon the proposed door exceeds each mine project specification. We advise each and every customer on the proposed door model and construction with a built-in safety tolerance. Nothing is left to chance. We are happy to report that in over 114 Years, AMD opposing wing door design has no incidents or accidents reported. Taking it one step further, AMD will certify and stamp each door design by a Professional Engineer (PE). All product designs are tested in a rigorous Finite Element Analysis (FEA) process using modeling, simulation, and complex calculations in understand how the mine doors will behave under extreme physical mine conditions. Nothing is left to chance.

Safety Conclusion

As Andrew Johnston, Goldcorp Safety Officer once said, “The most important thing to go down the mine every day is the miner, and the most important thing to come out of the mine is the miner. The softest thing that goes underground is you, that’s literally it. Everything else is rock and steel.” AMD takes this to heart.  We regularly make engineering, design, and safety improvements to enhance our product offering.  

Don’t leave it to chance. Consider all safety aspects when choosing a better and safer door design.  Work with a proven Original Equipment Manufacturer like AMD that engineers the highest of safety standards into your project.

Your miners, and your miners’ families thank you. Considering the alternative is not an option.